Process Errors Without Messages - Endress+Hauser PROFI BUS Proline Promag 53 PROFIBUS DP Operating Manual

Troubleshooting
Symptoms
!
Note!
You may have to change or correct certain settings of the function matrix in order to rectify faults. The functions outlined below, such as DISPLAY DAMPING, for
example, are described in detail in the "Description of Device Functions" manual.
Flow values are negative, even though
the fluid is flowing forwards through
the pipe.
Measured value reading fluctuates even
though flow is steady.
Measured-value reading or measured-
value output pulsates or fluctuates, e.g.
because of reciprocating pump,
peristaltic pump, diaphragm pump or
pump with similar delivery
characteristic.
There are differences between the
flowmeter's internal totalizer and the
external metering device.
Measured value reading shown on
display, even though the fluid is at a
standstill and the measuring tube is full.
Measured-value reading on display,
even though measuring tube is empty.
The current output signal is
always 4 mA, irrespective of the flow
signal at any given time.
The fault cannot be rectified or some
other fault not described above has
occurred.
In these instances, please contact your
Endress+Hauser service organization.
148
9.4

Process errors without messages

Rectification
1. Remote version:
– Switch off the power supply and check the wiring → Page 53 ff.
– If necessary, reverse the connections at terminals 41 and 42
2. Change the setting in the INSTALLATION DIRECTION SENSOR function accordingly
1. Check grounding and potential matching. → Page 65 ff.
2. Check the fluid for presence of gas bubbles.
3. TIME CONSTANT function → increase the value (→ OUTPUTS/CURRENT OUTPUT/CONFIGURATION)
4. DISPLAY DAMPING function → increase the value (→ USER INTERFACE/CONTROL/BASIC CONFIGURATION)
Perform the "Pulsating Flow" Quick Setup (only possible if a pulse/frequency output is available
). → Page 92
If the problem persists despite these measures, a pulsation damper will have to be installed between pump and measuring
device.
This symptom is due primarily to backflow in the piping because the pulse output cannot subtract in the STANDARD or
SYMMETRY measuring modes.
The problem can be solved as follows:
Allow for flow in both directions. Set the MEASURING MODE function to PULSATING FLOW for the pulse output in
question.
1. Check grounding and potential matching → Page 65 ff.
2. Check the fluid for presence of gas bubbles.
3. Activate the ON-VALUE LOW FLOW CUT OFF function, i.e. enter or increase the value for the low flow cut off (→
BASIC FUNCTIONS / PROCESS PARAMETERS / CONFIGURATION).
1. Perform empty-pipe/full-pipe adjustment and then switch on Empty Pipe Detection → Page 129
2. Remote version:
Check the terminals of the EPD cable → Page 53
3. Fill the measuring tube.
Value for creepage too high:
Reduce the corresponding value in the ON-VALUE LOW FLOW CUT OFF function.
The following options are available for tackling problems of this nature:
• Request the services of an Endress+Hauser service technician
If you contact our service organization to have a service technician sent out, please be ready to quote the following
information:
– Brief description of the fault
– Nameplate specifications: order code, serial number → Page 11 ff.
• Returning devices to Endress+Hauser
The required procedures must be carried out before you return a flowmeter requiring repair or calibration to
Endress+Hauser. → Page 159
Always enclose a duly completed "Declaration of contamination" form with the flowmeter. You will find a preprinted
form at the back of this Operating Manual.
• Replace transmitter electronics
Components in the measuring electronics defective → order spare parts → Page 150
Proline Promag 53 PROFIBUS DP/PA
Endress+Hauser